Drivetrain Latest Topicshttps://forums.hybridz.org/forum/83-drivetrain/Drivetrain Latest TopicsenR-200 Spline counts and mystery hlsdhttps://forums.hybridz.org/topic/70534-r-200-spline-counts-and-mystery-hlsd/Ok so I have been getting some info together for some drivetrain upgrades I am going to be doing into my recently purchased 73 240z. I have searched and this is what I have come up with as far as nissan diff centers to be swaped into an r-200

s15 short nose R-200 helical- 30 spline

cedric/gloria R-200 helical - 29 spline

240sx short nose R-200 open- 29 spline

280z & zx long nose r-200 open- 29 spline

z31t long nose r-200 lsd- 29 spline

n/a z32 short nose r-200 open- 29 spline

z32tt R-230 lsd- 30 spline

90-96 Q45 short nose r-200 lsd - 30 spline

89 R32 GT-R CLSD R-200 - 30 spline

r30 skyline longnose R-200- 29 spline

Now then if you will notice that from the info I have dug up the gloria r200 hlsd uses the same splines/size as the longnose r-200 out of a z. So this unit should be more of a direct swap with great nissan quality.

So my question is has anyone outside of this country ever seen one of these cars in the junker and can possibly confirm what is above.

Also if anyone can add to the list I will update it in this post for an easier search. Thanks

]]>70534Wed, 15 Oct 2008 07:45:06 +0000OBX Differential Inspection and Installationhttps://forums.hybridz.org/topic/88099-obx-differential-inspection-and-installation/What follows are my experiences with the OBX unit (part number LSD10528). I still suggest you read through the related threads (HERE and HERE), as they give a more complete overview of the issues/solutions. This writeup is also not in "install" order, so be sure to read through it completely before starting, so you don't miss a step. Additional pictorial guidance can be found on rbryant's writeup.

________________________________________________________________

First thing of note is that due to a copyright issue (assumed?) all of the gears are installed backwards in comparison to the quaife. This causes the axle gears to slam into the bellville washers on accel, presumably causing premature wear and failure.

Here is an illustration of the difference, (pic via batou)

Be sure when swapping all the gears around that BOTH axle circlip grooves are toward the inside of the case. This will ensure both axles will clip in properly.

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Second thing of note is the poor quality of the stock bellevelle washers and stock casing bolts. The combination of bolt stretching and the breaking of washers has been known to lead to premature failure in these units.

The solution is to replace these parts. rbryant sells replacement bolts and washers as a package HERE, or you can source your own or reuse the case bolts and get new bellevelle washers HERE.

The actual orientation of the washers IS NOT as important as the final preload once you get everything put back together. The machining tolerances of these units make it impossible to suggest a universal washer orientation. The best advice is to try one, test it, rinse repeat until you get the proper amount of preload. Suggestions for various orientations are littered throughout the two linked OBX threads, so find the one that works best for you.

A good way to quickly estimate the preload is by counting the number of turns on the case bolts. From rbryant's writeup:

The overall goal with the washers is that they get ~.8-1.5mm of preload. The bolts are a 1.25mm pitch so you can tell the preload based on the number of turns on the bolts. From the time that the washers become snug to the time when the case is fully clamped by counting turns on the bolt. One full turn is 1.25mm. This means we want .5 to 1.25 turns from when the washers start to compress until the case is fully clamped down.

Rbryant's original writeup suggestion for the R200 washer orientation DID NOT work for me, so again, measure your preload and pick your own orientation.

Examples of McMaster washer orientations:

John Scott - ())()(()

lbhsbZ - ((()()))

cygnusx1 - ()()(())

EMWHYROHEN - ))))((((

Stock Quaife - )()()()(

Examples of rbryant washer orientations:

())(() - (originally suggested)

)(())( - (what I ended up using)()()()

)()()(

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Also, if using a S30 or S130 ring gear, it will use the 10mm ring gear bolts. Some have said it is a good idea to use these spacers (10 needed) to take up the slack in the bolt hole, which was designed for 12mm bolts. If using a 300zx ring gear, it will use the 12mm ring gear bolts, and the spacers will not be necessary.

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All other steps pertaining to installing this LSD can be found in your FSM, as it is just like installing any other open carrier. Hopefully you can re-use your stock carrier bearings, as I couldn't find them anywhere for less than $60 EACH.

]]>88099Sun, 31 Jan 2010 18:12:15 +0000OBX vs Quaife (with pixors)https://forums.hybridz.org/topic/57834-obx-vs-quaife-with-pixors/It has been stated in the past that the OBX diff is a direct copy of the Quaife differential. OBX is a company that has a reputation of producing cheap chinese knockoffs of quality parts. I purchased an OBX diff for an R200 off of ebay (brand new) for $375, and I also purchased a brand new Quaife for an R200. Retail on the Quaife is $1495.00. I have a connection that saved me about $300. The only similarity I found was the design and the theory of operation. The parts are all pretty different, which leads me to believe that OBX actually employed some of the own engineering into this one.

When the OBX arrived, I noticed what appeared to be a missing bolt, and I also noticed that out of the 11 remaining bolts, 9 of them were marked 8.8 strength and the other 2 were not marked, and had noticably smaller heads. After disassembly, I found that the 2 odd bolts, aside from having smaller heads and no spec markings, were also too short. The appearance of the unit was acceptable...

until I opened the box containing the quaife and saw this...

I now understand why the Quaife costs 4 times as much as the OBX. I was hesitant to open up the Quaife, because they don't break and the warranty card says I shouldn't, but I decided to because there hasn't been a picture thread comparing the 2 side by side.

The first difference, obviously, is the appearance and finish quality of the assembly. The quaife looks like a diamond, while the OBX looks like a rock. The OBX only has Ten 12mm holes to mount the ring gear, so if you are using an early ring gear, you will need to make spacers to take up the extra room around the bolt. Some say this isn't necessary, but I don't think its a bad idea. The Quaife has 20 holes in the ring gear flange....so that you can use either the 10mm or 12mm ring gears. This was a nice touch.

The OBX uses a 2 piece case, with all 11 bolts from one side, while the Quaife uses a 3 piece case, consisting of basically 2 end caps and a solid center section, and uses 6 bolts to hold each cap onto the center section.

OBX is on the left, Quaife is on the right...with only the bolts and part of the case removed. The flash didn't work, so I'll try to get a better pic later.

Here is a shot of the pieces removed to take the previous picture, again, OBX is on the left, quaife is on the right.

Here are the sidegears from each diff. The OBX uses a gear that simply floats inside in the housing....only centered by the loose fitting axle. The quaife sidegear has a pilot which locates it in the housing. The OBX has longer teeth than the Quaife sidegear. OBX is on the left, Quaife is on the right.

Both units each use 12 helical gears....6 for each side, but they are a little different. The OBX helicals have almost 1/4 inch of chamfer on the edges of the gear teeth, while the Quaife has substantially less chamfer. Less chamfer means more surface area able to generate friction against the case. the Quaife also uses larger diameter gears, that have some sort of surface treatment. OBX is on the left, Quaife is on the right

Now for the washer stack. The Quaife uses 6 washers, stacked )()()(, while the OBX came with 8 washers stacked ((()())). The washers retainers on the Quaife are considerably larger in diameter and very slightly longer than the OBX retainers. See my other thread for my problems with the OBX washers.

Quaife washer stack

OBX and Quaife washer retainers

While the OBX uses a separate spacer to house the the washer retainers and washers:

The Quaife incorporates this into the case center section, so there is no spacer to float around:

Thats if for the pics....camara batteries went dead.

The Quaife has very finely ground mating surfaces, almost polished, everywhere....there is not a dirty cut or coarse finish anywhere on it. It appears that every component has been though a vibratory deburring process, and then polished...amazingly well. The Quaife came coated in the thick anti corrosive oil, which wiped off easily with a rag and solvent.

The OBX diff has only finish machined surfaces, which on cast iron tend to be very porous...and arrived with what appeared to be residual cutting oil soaked into the pores. When you try to wipe it off, your rag gets caught up in the rough surface. No post machining deburring or polishing was done to the case of the OBX. The gears look to have been deburred, but not polished.

I think that the OBX diff would be fine for lower TQ applications if some things were replaced on it. First off, the washers need to be replaced. I think the best solution for the washer issue would be to make a spacer for the middle and use only 2 bellville washers, one on each side. Second, the case bolts need to be replaced with something of a higher grade. The OBX bolts are M8 x 1.25 x 60mm, available from McMaster car in 12.9 strength. I have a theory that the reason that my washers were destroyed in the OBX was because the case bolts were weak and stretched, allowing exessive clearance in the washer pack under accel and then impacting them on decel. I don't have the brains to prove this yet, but I'm working on it. Another possible flaw I see in the OBX is the oil holes. The Quaife has more holes for gear oil to enter the assembly, and the holes in the Quaife are much larger than the OBX oil holes. When I reasemble the OBX, I'll be adding a few more oil holes in non-critical spots in the case.

The Quaife's M10 x 30 bolts are much less prone to stretch, and therefore the quaife is a much more ridgid unit that can handle more TQ.

Hereâ€™s the method I used for dealing with those pesky inner boot cups. I hope the following visual how-to helps those that are unsure how to proceed. I hope to use this format and document as much as I can as I go through the various rebuild projects on my car.

First, the tools:

A cutoff wheel

Snap Ring pliers

At least one small ball peen hammer

A flat chisel (flat round)

A cold chisel (sharp line)

CV band crimp pliers (not shown)

A vice is really helpful (not shown)

Here you see one completed axle and the one we will be working on today

The new boots weâ€™ll be installing. You will want these on hand before you begin. Some of the boot kits include the O-rings and some do not. Recommended are the Beck-Arnley parts that do:

3. When you spin one tire in your car because you donâ€™t have a limited slip, the side and pinion gears inside the carrier, aka spider gears, are moving really fast to allow that one wheel peel to happen. THE MOST FREQUENT CAUSE OF FAILURE IN OUR DIFFS IS RELATED TO THE SPIDER GEARS.

4. On the Nissan diffs, ring gear size is given in mm.

R160 = 160mm or 6.29â€ in diameter

R180 = 180mm or 7.08â€ in diameter

R190 = 190mm or 7.48â€ in diameter

R200 = 200mm or 7.87â€ in diameter

R230 = 230mm or 9.05â€ in diameter

SPIDER GEAR FAILURES EXPLAINED:

What we tend to see most often is that the cross pin which holds the spider gears comes loose by breaking it's retaining pin. When this happens the shaft can then move back and forth and will eventually wallow out the hole in the cast iron carrier. This causes misalignment of the spider gears which makes the gears grind on each other and puts a lot of metal shavings in the oil. As the gears wear on each other and get looser the pin gets looser. Once that happens the pin works its way out of the carrier and starts beating the inside of the case. Sometimes the pin breaks in half, sometimes it just bends, but that's the end of the differential. This problem is pretty well known in drag raced, open, 2 pinion carriers. Welding the diff or switching to an LSD generally alleviates this problem.

Here is a list of available diffs that you might (relatively) commonly find in a Z:

R160 - Originally came in 510s, Subarus. Lighter weight than stock Z diff

R180 - Came in 240, 260, 77-78 280Z automatic, and 280ZX automatic, among others. Also in the new WRX STi

R190 - Nissan Comp diff used in early 70's race cars and 432R's. Still some of these floating around.

The R160, R180, and R190 are straight bolt ins to any 240Z. The diffs are all the same length from the axle to the rear cover. None of these diffs require a different mustache bar.

The R160 is only a 6.3" ring gear, so it is quite small. The open diffs are susceptible to spider gear damage due to spinning one tire. Still, 510 guys have been putting this diff, especially the clutch LSD version out of mid to late 80s Subaru XT turbos, behind big motors for a long time with good results. Gary Savage reported using one of these for more than 10 years in his VG30DET 510 which had 300 ft/lbs torque at the wheels.

The R180 is the standard diff in any 240Z. The ring gear size is 7.08â€. The open diffs are susceptible to spider gear damage due to spinning one tire. While we have had members run 300+ hp and 260+ lb/ft of torque through these diffs in road racing applications, they are not commonly held to be particularly strong especially when the open version is used. One more pitfall here is the 2 pinion LSD. This â€œstreetâ€ LSD uses 2 pinions instead of 4 like the â€œcompâ€ version, and it is extremely fragile. The 4 pinion LSD is much more stout and the 2 pinion should be avoided if possible. V8 and big torque cars can use this diff on the street but it is not recommended for drag racing.

Newer R180s are availabe from the 84-88 200SX and have a large K cast into the top of the housing. They can be used in the Z with some modifications. The newer diffs use a stub shaft that plugs into the diff and is retained by a circlip, and the older diffs used a bolt in stub shaft.

CLIP IN AXLE VS BOLT IN AXLE R160s/180s

There are two ways to use the newer R180s with the original side stub shafts and half shafts. One is to convert the diff to the bolt in axles. The part that the bolts connect to is called a button, and the procedure to swap the buttons into a K diff is described below. These same procecures hold for LSD carriers, but the disassembly of the LSD is a bit more complicated. The other is to modify the stubs to use a spring clip, and then clip the axles in. http://www.betamotorsports.com has taken the effort out of this procedure by performing all the machine work. Just buy the new stubs and clip them in.

In addition to the bolt in axle issues, there is another difference between early and late R180s. Early R180's measure 110mm inside the ring gear. 77 and later model year R180s measure 115mm inside the ring gear. This minor change means that the ring and pinions won't swap between the early and later models. If you have an early diff you must use an early carrier, and if you have the later diff you must use a later carrier. It is possible to use a early carrier on a later ring gear with a spacer, but that is outside the scope of this thread.

Modification procedures to convert new K R180 to bolt in stub shafts:

1. Start with K R180:

2. Remove seal protectors and circlips:

3. Remove buttons from side gears in old differential and place them on the new side gears in the K R180:

4. Reassemble carrier with buttons in place. Now you can bolt in the side stubs just as you would on the original R180:

The R190 was a diff sold through Nissan Comp back in the 70â€™s and maybe 80â€™s too. It is a good option if you can find one, but they arenâ€™t very common. They come in a 4 pinion open diff which is much stronger than 2 pinion open, and a 2 and 4 pinion LSD version. Again, avoid the 2 pinion LSD. The H190 Detroit locker also fits in this differential, but this is a really rare combo. The Detroit locker R190 would be great for a drag racer if it could be found. It does ratchet quite harshly on cornering though.

The LONGNOSE R200 is the diff that started to appear in the 260 2+2 and continued through the 280Z and 280ZX manual, and also came standard in all Z31 cars as well. Some 200SXâ€™s also came with this diff, and probably others. This diff is strong enough for most Hybrid Z cars, and is by far the most popular swap. All of the 280Z and ZXâ€™s and 200SXâ€™s came with 2 pinion open diffs. These of course suffer the same weakness as the previous diffs. 87-89 300ZX Turbos came with clutch LSDâ€™s (CLSD). The Nissan CLSDs are all 4 pinion, and the pinion gears are very strong in the LSD. There have been complaints that the CLSD would start to slip like an open diff with more than 300 lb/ft of torque. This seems to be a problem with the clutch pack design. In order to save money it appears that the clutch packs were skimped upon, using a thick solid washer to make up a large portion of the clutch pack thickness. The result is that the tabs on the few clutches that are actually in use will break under heavy drag racing use. Some (only some) Nissan Comp diffs have a better more complete clutch pack, but how exactly one determines which have more clutches and which have fewer has yet to be determined. There has been at least one case of a racer buying a LSD from Nissan Comp and getting the shoddy clutch pack setup. Some members here have gone to the trouble to make their own clutches to replace the spacer in the LSD, which should provide a lot more strength for high torque applications. There is also a viscous LSD (VLSD) which came in the 88 SS version of the 300ZXT. This is a rare diff indeed and the spline count of the LSD unit is different than the CLSD or open diffs, so if you buy one, best to be sure you get the original CVâ€™s with the diff.

The R200 is wider than the stock R180 diff that comes in the 240Z, but most people use the stock halfshafts when they swap this diff in. This can lead to the halfshafts bottoming out which can cause handling issues. For more info read the R200 Handling Issues link here: http://www.betamotorsports.com/benchracing/index.html The solution here appears to be to use the CV joints from the 300ZX Turbo when installing into a 240Z.

The parts list needed to bolt in a longnose R200 into a 240Z is as follows:

1. mustache bar from 280Z with R200

2. yoke (companion flange) from 280Z with R200

3. rear cover from 280Z or ZX with R200

4. side stub shafts from 280Z or ZX with R200 to bolt up to stock halfshafts

FOR EARLY 70-71 Z's only, you need 5 -7.

5. Longer 72-78 driveshaft

6. Curved transverse link that sits right behind the diff from 72-78 Z

7. Flip front diff mount around on crossmember

5-7 are necessary because the early Z's had the diff mounted forward, and swapping to the R200 moves the diff rearward. Obviously if you buy a diff from a 280Z with an R200, it has everything you need except the mustache bar. If you buy the 300ZX diff, then you need the above pieces.

Another option is to convert to CV shafts. If you do that, then you need the CVs from the Z31 300ZX Turbo along with an adapter, and you no longer need #4. Adapters are available from http://www.modern-motorsports.com.'>http://www.modern-motorsports.com. There is also a way to convert to 280ZX Turbo CV's as well. These aren't as strong as the later CV's. Modern Motorsports has those adapters as well.

It is also possible to modify the rear transverse link to clear the finned cover of the 300ZXT rear cover. This requires a bit of fabrication, but is pretty easy and has the advantage of a larger sump and cooling fins to allow the diff to run cooler. If you do this then you don't need #3.

The longnose R200 diff has been used for extremely powerful drag racing cars, all the way up to 9 second Â¼ mile times, but it seems to be generally accepted that you can run 400 + lb/ft through them without any damage, except clutch damage in the case of the Z31T clutch LSD.

The SHORTNOSE R200 and R230 are entirely different from all of the above diffs. They are very similar with regards to installation, so weâ€™ll deal with them together. These diffs are as the name implies shorter, and so THESE ARE NOT A BOLT IN. The shorter length will require a new longer driveshaft. Most people buy this diff for the viscous LSD. While VLSDâ€™s are not as aggressive as CLSDâ€™s, they are fairly bulletproof, and donâ€™t have issues with clutch packs breaking. They are also much more readily available in the junkyards than the 87-89 Z31T longnose R200 with LSD. The open diffs have 4 pinion carriers so they are also more durable than an open 2 pinion diff, but the decision to go through all the hassle just to install a 4 pinion open diff would be questionable at best.

Installation of this diff is not for the faint of heart. It takes lots of fabrication to get this install completed. The mustache bar must be redrilled for the wider stud spacing on the short nose diff cover. This sounds easy, but the mustache bar is made from super hard spring steel and is very difficult to drill holes in. Most people take the diff to a machine shop to have this done. Then the diff must be spaced forward to clear the uprights for the rear suspension. The longnose cover does not bolt on, so it cannot be substituted.

The differential won't clear the link between the two rear control arm bushings. A custom link can be made, or this piece from http://www.arizonazcar.com can be used. It moves the brace between the control arm bushings up and out of the way:

The front mount is entirely up to you. Several parts suppliers have expressed interest in making a custom front diff mount for the short nose R200, but none has done it as of this time. Most people modify the original short nose front diff crossmember and use it. This is commonly done by building a cradle or frame that attaches the front S30 diff crossmember in front and the transverse link just inboard of the rear control arm bushings in the back. This is a simple ladder type frame and the original front crossmember is trimmed to fit into this ladder and welded in place.

Another way to mount the diff is to build a frame that sits over the top of the diff and attaches the chassis of the car. The frame then bolts to the stock bushings on the front of the diff. Here's an example:

Either way youâ€™re into some pretty serious fabrication, and due to the torque multiplication of the diff, the forces on this front mount can get EXTREME. There can be thousands of pounds of upward force on the front of the diff that the mount has to transfer to the chassis. This is not a job for a first time welder.

The CV shafts from the donor vehicles are too long to use in the S30 chassis, so custom CV shafts must be used. In order to get one set of CV shafts, it is necessary to obtain 4 inner CV shafts from an Infiniti Q45. If you are junkyard shopping, that means you are most likely going to buy 4 Q45 shafts, and throw away the shafts and the outer CV joint. Once the 4 inner shafts are obtained, a new shorter CV shaft is necessary. Moser makes this piece and it is available through http://www.modern-motorsports.com.'>http://www.modern-motorsports.com. Modern Motorsports also makes the necessary adapter to bolt the CV shaft to the companion flange at the wheel side of the CV shaft. Modern Motorsports has ensured that the shafts they sell fit both the R200 shortnose and the R230 shortnose, so there should be no issues with bottoming the shafts out or topping them out with either differential.

The Modern Motorsports CV shaft assembly:

The torque capacity of the shortnose R200 should be equivalent to the R200 longnose, which means it can handle a lot of abuse. 400 lb/ft should not be a problem with the R200 shortnose, and it will probably hold a good amount more if the VLSD is used. There is apparently another model of the R200 shortnose which has 5 bolt output flanges on the sides of the diff. This model should be avoided, since the CV adapters we have available use the 6 bolt flanges.

The R230 is bigger than a 9â€ Ford differential, so weâ€™re talking HUGE torque capacity here. I suppose weâ€™ll have to wait for someone to break one before weâ€™ll know for sure.

BACKHALVES/LIVE AXLES

With straight axles the sky is the limit with regards to torque capacity. Installing a straight axle in your Z is not a bolt in proposition and requires a lot more fabrication than the R200/R230 shortnose diffs. In brief and general terms, the procedure is as follows. The entire rear frame is replaced with a new rectangular tube frame. From this generally coilover springs and shocks are used to connect the frame to the differential. Then a linkage system is used to control the motion of the differential as the suspension moves up and down. The most popular of these is the 4 link, and this can be used in conjunction with a Panhard bar or alternatively a Watts linkage to locate the diff side to side. The benefit to going to a backhalf setup is nearly unlimited ability to build it up to hold more torque. Also the rear end can be â€œtubbedâ€ which means that the rear wheel wells can be made much larger in order to accommodate huge drag racing slicks.

Live axles were also fairly common in road racing Z cars in the GT2 category. This is because they could be had with a quick change rear end, allowing for gear ratio changes to suit a particular track without having to pull the entire differential out. Also there used to be a fairly severe weight penalty in the GT2 class for running independent rear suspension. Now that penalty has been reduced so it is likely that live axles wonâ€™t be as popular in the road racing Z cars of the future.

LIMITED SLIP DIFFERENTIAL CARRIERS

What are they, how do they work, which one is best? Hereâ€™s a brief rundown:

Nissan Clutch LSD: This is the most common type of LSD for R160, R180 and longnose R200 diffs. Nissan sells them through Nissan Competition Dept and NISMO. This is a 2 way limited slip, meaning that it limits slip both on acceleration and deceleration. It is torque sensing, and the more power you put to it the harder it locks up.

R160â€™s use a 3 pinion design and is generally regarded as very strong.

R180â€™s come in a 2 pinion and a 4 pinion version. The 2 pinion is weak and prone to breakage. The 4 pinion is very strong.

R200â€™s come in a 4 pinion version only, but there are several different clutch packs. It appears that the Z31T diff from the 87-89 300ZX Turbo came with a large spacer to take the place of several of the clutches in the stack. With powerful engines and slicks this can lead to stripping the teeth off of the clutches, making the diff no better than an open diff. NISMO and Nissan Comp sell another version which has more clutch disks and no spacers that should be a lot stronger, but there is some ambiguity as to what you will get when you order one. At least one person has reported buying an LSD from Nissan Comp and getting the spacers. The better diff with the improved clutch packs also has more aggressive lockup. One way to tell the two apart is to look at the ramps and the cross pin shaft shape.

This is the better more agressive unit, note the obtuse angle of the top and bottom of the cross pin:

This is the one with the large spacer in it, note the almost square ends:

Power Brute - This LSD is the same as the Nissan unit, and is imported from Japan. It is distributed by http://www.differentials.com and http://www.reiderracing.com, but again which version of the R200 diff youâ€™ll be receiving is somewhat ambiguous. Get the good clutch pack if you can.

Quaife - This is an entirely gear driven LSD. The way this works is that the side gears drive long pinion gears into the sides of the case. As long as there is traction to both wheels the pinion gears get driven into the case, and the friction from that action transfers the torque from one wheel to the other. This torque transfer can be measured and is frequently referred to as a torque bias ratio. The R diffs have a torque bias ratio of 5:1. Amazingly this diff is warranteed for life, even if the car is raced. The Quaife is a one way diff and does not lock up on decel.

OBX - Chinese knockoff of the Quaife. Some other car forums had reported manufacturing errors. Still in business?

PHANTOM GRIP - The Phantom Grip is an inexpensive part that converts an open diff to limited slip. The way this one works is it has two plates that slide in between the side gears of your open differential. In between the two plates are springs. The springs push against the side gears, and this makes it harder to rotate the side gears. The strength of the springs alone determines the amount of lockup, there is no torque sensing function in this one.

TORSEN - This LSD was available for a short time and there are just a few of these floating around, seems like most/all are for R200s. The Torsen diff is a gear driven LSD like the Quaife, but the one used in the Nissan diffs is designed in such a way that it is more like a 1.5 way and does provide some amount of lock up on decel. There have been reports of a new Subaru being fitted with a R200 torsen diff, and also it seems the S15 version of the 240SX has a Torsen as well, so we may be seeing more of these diffs hitting the market at good prices soon.

Torsen LSD:

NISSAN VLSD - Viscous LSDs are commonly available in the shortnose R200 and R230. They did also make an appearance in the 88 SS version of the 300ZX Turbo. The limited slip mechanism is passive meaning that it is not doing anything to limit slip until one wheel "starts" to spin. A brief description of how it works is to compare it to a viscous coupling like that in a torque converter. The faster one side wants to spin, the more the viscous coupling locks the two wheels together. VLSDâ€™s are not as grabby when they lock up and they arenâ€™t as positively locked either. In road racing applications the fluid can overheat and cause slippage. The fluid used in the coupling is independent from the rest of the differential oil and it can be changed in viscosity to affect the aggressiveness of the unit.

KAAZ/CUSCO â€“ These Japanese aftermarket parts manufacturers both make LSDs for the R diffs. They are commonly advertised for the 240SX which uses a shortnose R200, but the LSD can be used in a longnose R200 as well. If you purchase one of these diffs, make sure you get the replacement for 240SX with an OPEN DIFF. This will have the correct spline count for stock side stub shafts or Z31T CV shafts.

Both KAAZ and CUSCO produce LSDâ€™s in 1.5 way and 2 way variations. The 1.5 way doesnâ€™t lock the rear wheels together as hard under deceleration as it does under acceleration. This makes the car easier to handle when on the brakes hard. The clutch packs on these diffs are very impressive. They have a lot more and a lot larger clutch disks in them than the Nissan diffs so they should be extremely durable.

ARB Air Locker - ARB makes a selectable locker for the R180 and R200. This is an air powered unit that turns the diff from completely open to fully locked at the flip of a switch. The lockers have been around for a long time and are very popular with the rock crawling crowd. This means that they should be extremely strong, and this differential would be an EXCELLENT choice for a street/drag car, because it could be driven around town with the open differential and then locked solid for the track, and then switched back.

CV VS HALFSHAFT

The stock halfshafts that you might use on your 400hp V8 conversion are the same units that came on a 69 Datsun 510 with a L16 pushing all of about 100bhp. Thatâ€™s right. They are exactly the same. Surprisingly, they will withstand a hell of a lot of abuse, especially if the halfshaft angles are kept relatively mild. Preventing the suspension from compressing too far on hard drag race style launches and avoiding excessive negative camber are two ways to help keep the halfshafts alive.

In the 70 and 71 Z cars the diff was also mounted forward in the chassis. This means that there is another angle in the halfshafts. Nissan realized that this was causing vibration complaints and U-joint failures and moved the diff back until the halfshafts sat at a straight angle, curing this problem. If youâ€™re planning on running a high torque engine in your early Z, it is a good idea to move the diff back to get the proper alignment on the halfshafts. Still the halfshafts are definitely the weakest link in the drivetrain, so if youâ€™re pushing big power, or running real low, or have an extreme alignment, itâ€™s a good idea to step up to something better.

The original halfshafts:

The CV shafts first made their appearance in the Z line with the 280ZXT. This car got the tripod style CVs which have 3 large rollers arranged 120 degrees apart from each other. The 280ZXT CVâ€™s are more durable than the halfshafts and are a good upgrade. http://www.modern-motorsports.com makes an adapter which allows the CV shaft to be bolted to the companion flange on the stub axle (the wheel side connection for the halfshaft). The 280ZXT CV plugs into an open or CLSD R200. These CV joints have bulky housings and can interfere with rear swaybar end links. Some have simply put smaller end links on to get around this issue.

280ZXT CV shafts:

The Z31 got a different, stronger CV shaft. In addition to being stronger, the housing for the CV joint is smaller in diameter, and this means that it interferes with sway bar end links less. There are two different Z31 CV shafts. The normally aspirated Z31 uses a 6 bolt shaft. For whatever reason, these shafts are too long to be used in the S30 chassis. Donâ€™t get NA Z31 shafts. The Z31 turbo shafts have 4 bolts, and they are the right size to fit into the S30, using companion flange adapters from http://www.modern-motorsports.com.'>http://www.modern-motorsports.com.

Z31T CV shafts:

There has been some discussion about the Z31T shafts being too long. After measuring, it appears that this is a problem on the 240 for sure, and probably for the 260 and 280 as well. M2 Differentials (www.m2differentials.com) now manufactures some shorter 4340 chromoly shafts. These shafts are the correct length so that they put the outer CV right in the middle of its travel on a 240Z. If your shafts are too long, that means that the suspension stops moving when the CV bottoms. Using the CV shaft as the suspension bumpstop puts a lot of stress on the differential, the suspension, the stub axles and the wheel bearings.

STUB AXLES

The stub axle is the part that the wheel bolts to, and has a shaft that goes through the rear strut housing and the wheel bearings. There is a â€œcompanion flangeâ€ which fits onto the splined end of the stub axle. This companion flange is the part which the outboard end of the CV axle bolts to. The stub axles are next in line to the halfshafts as the weakest links in the drivetrain. In most R200 configurations, the halfshafts will go out first, then the stub axles, then the diff.

240s have the weakest stub axles with a smaller diameter 25 spline shaft. 260s got the 240 stubs for the first part of production, then later got the 280s 27 spline shafts. The 240 shafts have been used by people running V8 conversions for long periods of time without any failures, but as with all of these things, usage will likely limit how long the weaker parts can be successfully used. In other words, if you are drag racing on slicks, you probably want to step up.

280 stub axles can be installed in 240 struts with no modifications and the wheel bearings and seals are the same in both cases. This upgrades the inner part of the shaft from 25 to 27 spline.

4130 STUB AXLES

Above and beyond the 280 stub axle swap, http://www.modern-motorsports.com makes a 4130 chromoly stub axle and companion flange in 4 or 5 lug styles. The companion flange can be ordered to fit the 280ZXT CV shafts, the 300ZXT CV shafts, or the shortnose R200/R230 CV shafts. This is the strongest option available without resorting to a live axle swap or making a custom strut housing to fit a larger beefier axle shaft.

Modern Motorsport 4130 stub axles:

STUB AXLE FAILURE

Eric Neyerlin at http://www.zparts.com was nice enough to grant permission to show his photos of stub axle destruction. The stub axles usually tend to break on the inside where the compainion flange is. Usually when the stub axle breaks on the inside there is an odd noise similar to a broken U-joint that prompts the driver to investigate until the cause is found. The car may even still be driveable with the axle sheared in some cases. In other cases when the axle breaks the halfshaft falls away from the outside edge of the wheel and whips around beating the hell out of the control arm.

Picture of broken stub axle:

Close up of sheared edge:

The other weld on the stub axle is located where the flange is connected to the shaft. If this part of the stub fails you're in trouble. The whole wheel and brake can lean right in until it hits some part of the suspension or wheel well. Here is a picture of what happens when the flange weld fails:

R160/180/200 LONGNOSE DIFF MOUNT

The stock front differential mount on the Z is a source of constant exacerbation for Z owners. The diff mount does not have a failsafe built into it so by design when the mount comes apart there is nothing to prevent the nose of the diff from climbing. Nissan was kind enough to â€œfixâ€ that problem by adding a strap over the top of the diff which helps limit the lifting at the front of the diff. These two parts combined do a marginal job of controlling the diff even under the â€œabuseâ€ that stock power levels can put to them. Any increase in power levels should be accompanied by some attention to the front diff mount.

SOLID DIFF MOUNTS

These are sold by several aftermarket parts suppliers including http://www.arizonazcar.com and http://www.zcarparts.com. They will absolutely prevent the nose of the diff from lifting, but they also transmit lots of noise into the cabin, so much that some members here have reported feeling physically ill after only 10 minutes exposure to the noise. Regardless of these issues, this is a popular race part for Z cars, and there are quite a few people who do use these mounts on the street.

ALTERNATIVE DIFF MOUNTS

The creativity of our members cannot be overestimated and some of the easiest and simplest solutions to this problem come from our membersâ€™ garages. Probably the simplest solution comes from Clifton, who welded two tabs, one in front and one in back, to the vertical face of the diff mount. Then he drilled a hole in the tabs and ran a bolt through the two tabs. The bolt is trapped underneath the crossmember, so the diff can only lift until the bolt touches the crossmember. Simple solution and easy to make. I could not find a picture of this diff mount. I know I've seen it before. If you have a link post it up please.

Another good one is the clamshell design. A U shaped piece of metal is fitted below the front diff crossmember, and a rubber pad is installed on the new piece. This is then bolted or welded to the existing vertical flanges of the diff mount, similarly to Cliftonâ€™s solution. The advantage here is that the rubber isolates some noise from transmitting through the bolt and into the cabin. Itâ€™s possible a piece of fuel or radiator hose over the bolt in Cliftonâ€™s design might have just about the same effect. Click here for pictures and an explanation of the clamshell design: http://album.hybridz.org/showphoto.php?photo=2501

Either way both are simple and well worth the effort.

There is also Ron Tyler's design, which is more like the pinion snubber that you would find on an American car with a solid axle. This piece bolts to the chassis and the mount hangs down, where the diff bolts to it. This works great because the nose of the diff moves UP when torque is applied so torque doesn't rip the mount apart.

Pros:

- It isn't solid, so you get vibration isolation ALL THE TIME.

- It allows the front of the differential to be lowered so that the minimum and acceptable driveshaft u-joint angles can be obtained for a JTR V8 swap.

- It allows you to modifiy/partially remove the front diff crossmember for mor exhaust clearance.

- It bolts right in (in most cases).

Cons:

- It requires welding.

- It may take some massaging to fit into certain early 240Zs? So it may be best to build it on the car.

ALL PICTURES WERE TAKEN FROM THE HYBRIDZ ALBUM. IF YOU DON'T WANT YOUR PICTURE USED, LET ME KNOW AND I'LL REMOVE IT.

I COULD NOT FIND PICTURES OF ALL THE DIFFERENTIALS, OR WEIGHTS FOR ALL OF THE VARIATIONS. THIS IS A HELL OF A LOT OF INFO TO COVER, SO I WOULD NOT BE SURPRISED IF THERE ARE MISTAKES/OMISSIONS HERE. IF YOU HAVE THE TIME, READ IT OVER SO THAT IT CAN BE CORRECTED.

]]>49194Wed, 20 Sep 2006 00:34:33 +0000The dreaded "diff" CLUNKhttps://forums.hybridz.org/topic/105207-the-dreaded-diff-clunk/Z cars are prone to clunking noises when they transition on and off power. There are many causes for the clunk, but the most common suspect that is almost never guilty is the differential itself. Time and time again we read about someone who "checks the backlash" in the differential by rocking the driveshaft back and forth, or jacks up one wheel and rocks it back and forth and thinks that they've found the source of the noise. Occasionally one of these people will take the diff out and wonder why they can't reproduce the clunk with the diff out of the car, or how it is possible that the backlash is in spec. Some more unlucky people go to the trouble of replacing the whole differential with a known good unit or worse, replacing all of the bearings in the differential, which is an expensive job, only to find out that the clunk is still there when they're all done.

Checking backlash with the diff installed is very very difficult; I would say impossible. If you grab the driveshaft and turn it back and forth, you're probably not going to be able to isolate the feel the backlash because of everything else moving, and you probably can't move the pinion enough to isolate the backlash without everything else also moving. First you have to overcome the resistance in the transmission, and by the time you do that and the shaft starts to move, you've already put too much force on the pinion to just move the pinion alone without also moving the ring gear. So when you move the driveshaft, what you're likely doing is moving the transmission gears until they lock solid, the driveshaft splines and u-joints, the pinion flange and pinion splines, the ring and pinion, the pinion gears and the cross pin shaft, the diff output stubs and the side gear splines, the CV joints or u-joints on the halfshafts, the stub axle and companion flange splines, wheel bearings, and any brake slack that might get taken up. It's not a good test of backlash, and is probably only good for finding a very big problem somewhere such as a u-joint that is about to fall out.

Likewise on the jacking one side of the car up and twisting the raised wheel back and forth. You're going to feel any and all slack from the wheel on one side to the wheel on the other. Slack could be coming from stub axle/companion flange splines for both sides, wheel bearings for both sides, CV or u-joints for both sides, output stub to side gear splines for both sides, and spider gears (and there is more slack in the spiders if it's an LSD). Some of this slack or gear lash is absolutely necessary. The transmission gears, ring and pinion, and spider gears in the diff MUST have lash, otherwise they'll burn up.

Even on a bench with the cover off and rocking the ring gear to check backlash you need to be a little careful. The 87 FSM says backlash on the R200 is .0051" to .0071", and getting the carrier to rock back and forth such a small amount without turning the pinion requires a bit of attention.

There are cases where diff backlash is a problem. There are many more cases (common enough drag racing issue that it shows up on the forums from time to time) where the cross pin shaft on the carrier wallows out its hole, and this leads to a larger amount of pinion rotation before the outputs begin to move.

More likely though, the ring and pinion is not the cause of your clunking. So what is? Well, it could be any number of things, but we can make a list of the most common issues pretty easily.

1. Diff strap/front diff mount. Itâ€™s hard to imagine that Nissan sold a million Z cars with this kluged design, but they did. The diff mount is below the front of the differential housing and the nose of the diff wants to lift when you apply power to it. The mount is rubber and tears pretty easily, so Nissan added a strap over the top of the diff to limit the movement. This is a less than satisfactory fix in practice, and over time or with added power the straps break and the mounts tear, and the nose of the diff can lift surprisingly far up. It can raise up so high that the driveshaft hits the transmission tunnel. Solutions: Ron Tylerâ€™s diff mount (which he designed but other people are now producing), clamshell design diff mount addition where a bottom half is added to the diff mount which curves under the diff crossmember and prevents the mount from moving up, solid diff mounts also work but are generally not recommended because they put a lot of noise into the cabin and can cause stress at the crossmember causing it to break, and beefier replacement straps (usually metal or chain).

2. Mustache bar bushings. The diff hangs in the rear on the mustache bar. The mustache bar is insulated from the frame by rubber bushings, and they can wear out. These are typically replaced with polyurethane, which might solve a clunk but also transfers more diff noise into the car.

3. U-Joints. Worn driveshaft or halfshaft u-joints will definitely clunk on accel/decel. Replace as necessary. Just as checking backlash is difficult with the diff installed, I find checking u-joints on installed shafts damn near impossible. I have a friend who swears he can do it, but I always take the shaft out.

4. Control arm bushings. If the control arm bushings are worn out, they can allow movement which can cause a clunk. They are a royal pain in the ass to replace. Search: â€œspindle pinâ€ for more details.

5. Loose bolts. A lot of these clunks are caused by the two big nuts that hold the diff to the mustache bar coming loose, or loose driveshaft bolts. Also check diff cover bolts and suspension mounting bolts.

If you have a clunk and youâ€™ve gotten to this point and havenâ€™t found the source, youâ€™re into the weird stuff. At this point you need to work your way through the whole driveline looking for problems. Look for loose splines on drive shafts and axles, bad driveline mounts, anything. Arne over at www.classiczcars.com even reported that his clunk turned out to be caused by a woodruff key inside the transmission. â€œMine was in the transmission itself. The woodruff keys that locate the drive gear on the front of the countershaft were worn, allowing the the gear to move on the countershaft. Clunk once under forward torque, and thud back under the reverse. Sounded for all the world like the clunk was coming from much farther back.â€

Dealing with a clunk is like pulling the spindle pins on the rear control arms. It's a not so glamourous rite of passage that most of us go through. I'm hoping others will add their oddball clunk causes as well.

]]>105207Thu, 23 Feb 2012 02:11:18 +0000Differential / CV / LSD / HP / Torque / R160 / R180 / R200 / R230 / Diff Mount FAQhttps://forums.hybridz.org/topic/50499-differential-cv-lsd-hp-torque-r160-r180-r200-r230-diff-mount-faq/This question is extremely common and has no perfect answer, but this post is intended to relate what is typical amongst Hybrid Z'ers. A couple of basic points to start with:1. Torque kills diffs, not hp.2. The heavier your car is, the bigger diff you should get3. When you spin one tire in your car because you don’t have a limited slip, the side and pinion gears inside the carrier, aka spider gears, are moving really fast to allow that one wheel peel to happen. THE MOST FREQUENT CAUSE OF FAILURE IN OUR DIFFS IS RELATED TO THE SPIDER GEARS.4. On the Nissan diffs, ring gear size is given in mm.R160 = 160mm or 6.29” in diameterR180 = 180mm or 7.08” in diameterR190 = 190mm or 7.48” in diameterR200 = 200mm or 7.87” in diameterR230 = 230mm or 9.05” in diameter

SPIDER GEAR FAILURES EXPLAINED:

What we tend to see most often is that the cross pin which holds the spider gears comes loose by breaking it's retaining pin. When this happens the shaft can then move back and forth and will eventually wallow out the hole in the cast iron carrier. This causes misalignment of the spider gears which makes the gears grind on each other and puts a lot of metal shavings in the oil. As the gears wear on each other and get looser the pin gets looser. Once that happens the pin works its way out of the carrier and starts beating the inside of the case. Sometimes the pin breaks in half, sometimes it just bends, but that's the end of the differential. This problem is pretty well known in drag raced, open, 2 pinion carriers. Welding the diff or switching to an LSD generally alleviates this problem.

Here is a list of available diffs that you might (relatively) commonly find in a Z:

The R160, R180, and R190 are straight bolt ins to any 240Z. The diffs are all the same length from the axle to the rear cover. None of these diffs require a different mustache bar.

The R160 is only a 6.3" ring gear, so it is quite small. The open diffs are susceptible to spider gear damage due to spinning one tire. Still, 510 guys have been putting this diff, especially the clutch LSD version out of mid to late 80s Subaru XT turbos, behind big motors for a long time with good results. Gary Savage reported using one of these for more than 10 years in his VG30DET 510 which had 300 ft/lbs torque at the wheels.

The R180 is the standard diff in any 240Z. The ring gear size is 7.08”. The open diffs are susceptible to spider gear damage due to spinning one tire. While we have had members run 300+ hp and 260+ lb/ft of torque through these diffs in road racing applications, they are not commonly held to be particularly strong especially when the open version is used. One more pitfall here is the 2 pinion LSD. This “street” LSD uses 2 pinions instead of 4 like the “comp” version, and it is extremely fragile. The 4 pinion LSD is much more stout and the 2 pinion should be avoided if possible. V8 and big torque cars can use this diff on the street but it is not recommended for drag racing.

Newer R180s are availabe from the 84-88 200SX and have a large K cast into the top of the housing. They can be used in the Z with some modifications. The newer diffs use a stub shaft that plugs into the diff and is retained by a circlip, and the older diffs used a bolt in stub shaft.

CLIP IN AXLE VS BOLT IN AXLE R160s/180s

There are two ways to use the newer R180s with the original side stub shafts and half shafts. One is to convert the diff to the bolt in axles. The part that the bolts connect to is called a button, and the procedure to swap the buttons into a K diff is described below. These same procecures hold for LSD carriers, but the disassembly of the LSD is a bit more complicated. The other is to modify the stubs to use a spring clip, and then clip the axles in. http://www.betamotorsports.com has taken the effort out of this procedure by performing all the machine work. Just buy the new stubs and clip them in.

In addition to the bolt in axle issues, there is another difference between early and late R180s. Early R180's measure 110mm inside the ring gear. 77 and later model year R180s measure 115mm inside the ring gear. This minor change means that the ring and pinions won't swap between the early and later models. If you have an early diff you must use an early carrier, and if you have the later diff you must use a later carrier. It is possible to use a early carrier on a later ring gear with a spacer, but that is outside the scope of this thread.

Modification procedures to convert new K R180 to bolt in stub shafts:

1. Start with K R180:

2. Remove seal protectors and circlips:

3. Remove buttons from side gears in old differential and place them on the new side gears in the K R180:

4. Reassemble carrier with buttons in place. Now you can bolt in the side stubs just as you would on the original R180:

The R190 was a diff sold through Nissan Comp back in the 70’s and maybe 80’s too. It is a good option if you can find one, but they aren’t very common. They come in a 4 pinion open diff which is much stronger than 2 pinion open, and a 2 and 4 pinion LSD version. Again, avoid the 2 pinion LSD. The H190 Detroit locker also fits in this differential, but this is a really rare combo. The Detroit locker R190 would be great for a drag racer if it could be found. It does ratchet quite harshly on cornering though.

The LONGNOSE R200 is the diff that started to appear in the 260 2+2 and continued through the 280Z and 280ZX manual, and also came standard in all Z31 cars as well. Some 200SX’s also came with this diff, and probably others. This diff is strong enough for most Hybrid Z cars, and is by far the most popular swap. All of the 280Z and ZX’s and 200SX’s came with 2 pinion open diffs. These of course suffer the same weakness as the previous diffs. 87-89 300ZX Turbos came with clutch LSD’s (CLSD). The Nissan CLSDs are all 4 pinion, and the pinion gears are very strong in the LSD. There have been complaints that the CLSD would start to slip like an open diff with more than 300 lb/ft of torque. This seems to be a problem with the clutch pack design. In order to save money it appears that the clutch packs were skimped upon, using a thick solid washer to make up a large portion of the clutch pack thickness. The result is that the tabs on the few clutches that are actually in use will break under heavy drag racing use. Some (only some) Nissan Comp diffs have a better more complete clutch pack, but how exactly one determines which have more clutches and which have fewer has yet to be determined. There has been at least one case of a racer buying a LSD from Nissan Comp and getting the shoddy clutch pack setup. Some members here have gone to the trouble to make their own clutches to replace the spacer in the LSD, which should provide a lot more strength for high torque applications. There is also a viscous LSD (VLSD) which came in the 88 SS version of the 300ZXT. This is a rare diff indeed and the spline count of the LSD unit is different than the CLSD or open diffs, so if you buy one, best to be sure you get the original CV’s with the diff.

The R200 is wider than the stock R180 diff that comes in the 240Z, but most people use the stock halfshafts when they swap this diff in. This can lead to the halfshafts bottoming out which can cause handling issues. For more info read the R200 Handling Issues link here: http://www.betamotorsports.com/benchracing/index.html The solution here appears to be to use the CV joints from the 300ZX Turbo when installing into a 240Z.

The parts list needed to bolt in a longnose R200 into a 240Z is as follows:

1. mustache bar from 280Z with R2002. yoke (companion flange) from 280Z or 280ZX with R2003. rear cover from 280Z or ZX with R2004. side stub shafts from 280Z or ZX with R200 to bolt up to stock halfshaftsFOR EARLY 70-71 Z's only, you need 5 -7.5. Longer 72-78 driveshaft6. Curved transverse link that sits right behind the diff from 72-78 Z7. Flip front diff mount around on crossmember

5-7 are necessary because the early Z's had the diff mounted forward, and swapping to the R200 moves the diff rearward. Obviously if you buy a diff from a 280Z with an R200, it has everything you need except the mustache bar. If you buy the 300ZX diff, then you need the above pieces.

Another option is to convert to CV shafts. If you do that, then you need the CVs from the Z31 300ZX Turbo along with an adapter, and you no longer need #4. Adapters are available from http://www.modern-motorsports.com.'>http://www.modern-motorsports.com. There is also a way to convert to 280ZX Turbo CV's as well. These aren't as strong as the later CV's. Modern Motorsports has those adapters as well.

It is also possible to modify the rear transverse link to clear the finned cover of the 300ZXT rear cover. This requires a bit of fabrication, but is pretty easy and has the advantage of a larger sump and cooling fins to allow the diff to run cooler. If you do this then you don't need #3.

The longnose R200 diff has been used for extremely powerful drag racing cars, all the way up to 9 second Â¼ mile times, but it seems to be generally accepted that you can run 400 + lb/ft through them without any damage, except clutch damage in the case of the Z31T clutch LSD.

The SHORTNOSE R200 and R230 are entirely different from all of the above diffs. They are very similar with regards to installation, so we’ll deal with them together. These diffs are as the name implies shorter, and so THESE ARE NOT A BOLT IN. The shorter length will require a new longer driveshaft. Most people buy this diff for the viscous LSD. While VLSD’s are not as aggressive as CLSD’s, they are fairly bulletproof, and don’t have issues with clutch packs breaking. They are also much more readily available in the junkyards than the 87-89 Z31T longnose R200 with LSD. The open diffs have 4 pinion carriers so they are also more durable than an open 2 pinion diff, but the decision to go through all the hassle just to install a 4 pinion open diff would be questionable at best.

Installation of this diff is not for the faint of heart. It takes lots of fabrication to get this install completed. The mustache bar must be redrilled for the wider stud spacing on the short nose diff cover. This sounds easy, but the mustache bar is made from super hard spring steel and is very difficult to drill holes in. Most people take the diff to a machine shop to have this done. Then the diff must be spaced forward to clear the uprights for the rear suspension. The longnose cover does not bolt on, so it cannot be substituted.

The differential won't clear the link between the two rear control arm bushings. A custom link can be made, or this piece from http://www.arizonazcar.com can be used. It moves the brace between the control arm bushings up and out of the way:

The front mount is entirely up to you. Several parts suppliers have expressed interest in making a custom front diff mount for the short nose R200, but none has done it as of this time. Most people modify the original short nose front diff crossmember and use it. This is commonly done by building a cradle or frame that attaches the front S30 diff crossmember in front and the transverse link just inboard of the rear control arm bushings in the back. This is a simple ladder type frame and the original front crossmember is trimmed to fit into this ladder and welded in place.

Another way to mount the diff is to build a frame that sits over the top of the diff and attaches the chassis of the car. The frame then bolts to the stock bushings on the front of the diff. Here's an example:

Either way you’re into some pretty serious fabrication, and due to the torque multiplication of the diff, the forces on this front mount can get EXTREME. There can be thousands of pounds of upward force on the front of the diff that the mount has to transfer to the chassis. This is not a job for a first time welder.

The CV shafts from the donor vehicles are too long to use in the S30 chassis, so custom CV shafts must be used. In order to get one set of CV shafts, it is necessary to obtain 4 inner CV shafts from an Infiniti Q45. If you are junkyard shopping, that means you are most likely going to buy 4 Q45 shafts, and throw away the shafts and the outer CV joint. Once the 4 inner shafts are obtained, a new shorter CV shaft is necessary. Moser makes this piece and it is available through http://www.modern-motorsports.com.'>http://www.modern-motorsports.com. Modern Motorsports also makes the necessary adapter to bolt the CV shaft to the companion flange at the wheel side of the CV shaft. Modern Motorsports has ensured that the shafts they sell fit both the R200 shortnose and the R230 shortnose, so there should be no issues with bottoming the shafts out or topping them out with either differential.The Modern Motorsports CV shaft assembly:

The torque capacity of the shortnose R200 should be equivalent to the R200 longnose, which means it can handle a lot of abuse. 400 lb/ft should not be a problem with the R200 shortnose, and it will probably hold a good amount more if the VLSD is used. There is apparently another model of the R200 shortnose which has 5 bolt output flanges on the sides of the diff. This model should be avoided, since the CV adapters we have available use the 6 bolt flanges.

The R230 is bigger than a 9” Ford differential, so we’re talking HUGE torque capacity here. I suppose we’ll have to wait for someone to break one before we’ll know for sure.

BACKHALVES/LIVE AXLES

With straight axles the sky is the limit with regards to torque capacity. Installing a straight axle in your Z is not a bolt in proposition and requires a lot more fabrication than the R200/R230 shortnose diffs. In brief and general terms, the procedure is as follows. The entire rear frame is replaced with a new rectangular tube frame. From this generally coilover springs and shocks are used to connect the frame to the differential. Then a linkage system is used to control the motion of the differential as the suspension moves up and down. The most popular of these is the 4 link, and this can be used in conjunction with a Panhard bar or alternatively a Watts linkage to locate the diff side to side. The benefit to going to a backhalf setup is nearly unlimited ability to build it up to hold more torque. Also the rear end can be “tubbed” which means that the rear wheel wells can be made much larger in order to accommodate huge drag racing slicks.

Live axles were also fairly common in road racing Z cars in the GT2 category. This is because they could be had with a quick change rear end, allowing for gear ratio changes to suit a particular track without having to pull the entire differential out. Also there used to be a fairly severe weight penalty in the GT2 class for running independent rear suspension. Now that penalty has been reduced so it is likely that live axles won’t be as popular in the road racing Z cars of the future.

LIMITED SLIP DIFFERENTIAL CARRIERS

What are they, how do they work, which one is best? Here’s a brief rundown:

Nissan Clutch LSD: This is the most common type of LSD for R160, R180 and longnose R200 diffs. Nissan sells them through Nissan Competition Dept and NISMO. This is a 2 way limited slip, meaning that it limits slip both on acceleration and deceleration. It is torque sensing, and the more power you put to it the harder it locks up.

R160’s use a 3 pinion design and is generally regarded as very strong.R180’s come in a 2 pinion and a 4 pinion version. The 2 pinion is weak and prone to breakage. The 4 pinion is very strong.R200’s come in a 4 pinion version only, but there are several different clutch packs. It appears that the Z31T diff from the 87-89 300ZX Turbo came with a large spacer to take the place of several of the clutches in the stack. With powerful engines and slicks this can lead to stripping the teeth off of the clutches, making the diff no better than an open diff. NISMO and Nissan Comp sell another version which has more clutch disks and no spacers that should be a lot stronger, but there is some ambiguity as to what you will get when you order one. At least one person has reported buying an LSD from Nissan Comp and getting the spacers. The better diff with the improved clutch packs also has more aggressive lockup. One way to tell the two apart is to look at the ramps and the cross pin shaft shape.This is the better more agressive unit, note the obtuse angle of the top and bottom of the cross pin:

This is the one with the large spacer in it, note the almost square ends:

Power Brute - This LSD is the same as the Nissan unit, and is imported from Japan. It is distributed by http://www.differentials.com and http://www.reiderracing.com, but again which version of the R200 diff you’ll be receiving is somewhat ambiguous. Get the good clutch pack if you can.

Quaife - This is an entirely gear driven LSD. The way this works is that the side gears drive long pinion gears into the sides of the case. As long as there is traction to both wheels the pinion gears get driven into the case, and the friction from that action transfers the torque from one wheel to the other. This torque transfer can be measured and is frequently referred to as a torque bias ratio. The R diffs have a torque bias ratio of 5:1. Amazingly this diff is warranteed for life, even if the car is raced. The Quaife is a one way diff and does not lock up on decel.

OBX - Chinese knockoff of the Quaife. Some other car forums had reported manufacturing errors. Still in business?

PHANTOM GRIP - The Phantom Grip is an inexpensive part that converts an open diff to limited slip. The way this one works is it has two plates that slide in between the side gears of your open differential. In between the two plates are springs. The springs push against the side gears, and this makes it harder to rotate the side gears. The strength of the springs alone determines the amount of lockup, there is no torque sensing function in this one.

TORSEN - This LSD was available for a short time and there are just a few of these floating around, seems like most/all are for R200s. The Torsen diff is a gear driven LSD like the Quaife, but the one used in the Nissan diffs is designed in such a way that it is more like a 1.5 way and does provide some amount of lock up on decel. There have been reports of a new Subaru being fitted with a R200 torsen diff, and also it seems the S15 version of the 240SX has a Torsen as well, so we may be seeing more of these diffs hitting the market at good prices soon.Torsen LSD:

NISSAN VLSD - Viscous LSDs are commonly available in the shortnose R200 and R230. They did also make an appearance in the 88 SS version of the 300ZX Turbo. The limited slip mechanism is passive meaning that it is not doing anything to limit slip until one wheel starts to spin. A brief description of how it works is to compare it to a viscous coupling like that in a torque converter. The faster one side wants to spin, the more the viscous coupling locks the two wheels together. VLSD’s are not as grabby when they lock up and they aren’t as positively locked either. In road racing applications the fluid can overheat and cause slippage. The fluid used in the coupling is independent from the rest of the differential oil and it can be changed in viscosity to affect the aggressiveness of the unit.

KAAZ/CUSCO – These Japanese aftermarket parts manufacturers both make LSDs for the R diffs. They are commonly advertised for the 240SX which uses a shortnose R200, but the LSD can be used in a longnose R200 as well. If you purchase one of these diffs, make sure you get the replacement for 240SX with an OPEN DIFF. This will have the correct spline count for stock side stub shafts or Z31T CV shafts.

Both KAAZ and CUSCO produce LSD’s in 1.5 way and 2 way variations. The 1.5 way doesn’t lock the rear wheels together as hard under deceleration as it does under acceleration. This makes the car easier to handle when on the brakes hard. The clutch packs on these diffs are very impressive. They have a lot more and a lot larger clutch disks in them than the Nissan diffs so they should be extremely durable.

ARB Air Locker - ARB makes a selectable locker for the R180 and R200. This is an air powered unit that turns the diff from completely open to fully locked at the flip of a switch. The lockers have been around for a long time and are very popular with the rock crawling crowd. This means that they should be extremely strong, and this differential would be an EXCELLENT choice for a street/drag car, because it could be driven around town with the open differential and then locked solid for the track, and then switched back.

CV VS HALFSHAFT

The stock halfshafts that you might use on your 400hp V8 conversion are the same units that came on a 69 Datsun 510 with a L16 pushing all of about 100bhp. That’s right. They are exactly the same. Surprisingly, they will withstand a hell of a lot of abuse, especially if the halfshaft angles are kept relatively mild. Preventing the suspension from compressing too far on hard drag race style launches and avoiding excessive negative camber are two ways to help keep the halfshafts alive.

In the 70 and 71 Z cars the diff was also mounted forward in the chassis. This means that there is another angle in the halfshafts. Nissan realized that this was causing vibration complaints and U-joint failures and moved the diff back until the halfshafts sat at a straight angle, curing this problem. If you’re planning on running a high torque engine in your early Z, it is a good idea to move the diff back to get the proper alignment on the halfshafts. Still the halfshafts are definitely the weakest link in the drivetrain, so if you’re pushing big power, or running real low, or have an extreme alignment, it’s a good idea to step up to something better.

The original halfshafts:

The CV shafts first made their appearance in the Z line with the 280ZXT. This car got the tripod style CVs which have 3 large rollers arranged 120 degrees apart from each other. The 280ZXT CV’s are more durable than the halfshafts and are a good upgrade. http://www.modern-motorsports.com makes an adapter which allows the CV shaft to be bolted to the companion flange on the stub axle (the wheel side connection for the halfshaft). The 280ZXT CV plugs into an open or CLSD R200. These CV joints have bulky housings and can interfere with rear swaybar end links. Some have simply put smaller end links on to get around this issue.

280ZXT CV shafts:

The Z31 got a different, stronger CV shaft. In addition to being stronger, the housing for the CV joint is smaller in diameter, and this means that it interferes with sway bar end links less. There are two different Z31 CV shafts. The normally aspirated Z31 uses a 6 bolt shaft. For whatever reason, these shafts are too long to be used in the S30 chassis. Don’t get NA Z31 shafts. The Z31 turbo shafts have 4 bolts, and they are the right size to fit into the S30, using companion flange adapters from http://www.modern-motorsports.com.'>http://www.modern-motorsports.com.

Z31T CV shafts:

STUB AXLES

The stub axle is the part that the wheel bolts to, and has a shaft that goes through the rear strut housing and the wheel bearings. There is a “companion flange” which fits onto the splined end of the stub axle. This companion flange is the part which the outboard end of the CV axle bolts to. The stub axles are next in line to the halfshafts as the weakest links in the drivetrain. In most R200 configurations, the halfshafts will go out first, then the stub axles, then the diff.

240s have the weakest stub axles with a smaller diameter 25 spline shaft. 260s got the 240 stubs for the first part of production, then later got the 280s 27 spline shafts. The 240 shafts have been used by people running V8 conversions for long periods of time without any failures, but as with all of these things, usage will likely limit how long the weaker parts can be successfully used. In other words, if you are drag racing on slicks, you probably want to step up.

280 stub axles can be installed in 240 struts with no modifications and the wheel bearings and seals are the same in both cases. This upgrades the inner part of the shaft from 25 to 27 spline.

4130 STUB AXLES

Above and beyond the 280 stub axle swap, http://www.modern-motorsports.com makes a 4130 chromoly stub axle and companion flange in 4 or 5 lug styles. The companion flange can be ordered to fit the 280ZXT CV shafts, the 300ZXT CV shafts, or the shortnose R200/R230 CV shafts. This is the strongest option available without resorting to a live axle swap or making a custom strut housing to fit a larger beefier axle shaft.Modern Motorsport 4130 stub axles:

STUB AXLE FAILURE

Eric Neyerlin at http://www.zparts.com was nice enough to grant permission to show his photos of stub axle destruction. The stub axles usually tend to break on the inside where the compainion flange is. Usually when the stub axle breaks on the inside there is an odd noise similar to a broken U-joint that prompts the driver to investigate until the cause is found. The car may even still be driveable with the axle sheared in some cases. In other cases when the axle breaks the halfshaft falls away from the outside edge of the wheel and whips around beating the hell out of the control arm.

Picture of broken stub axle:

Close up of sheared edge:

The other weld on the stub axle is located where the flange is connected to the shaft. If this part of the stub fails you're in trouble. The whole wheel and brake can lean right in until it hits some part of the suspension or wheel well. Here is a picture of what happens when the flange weld fails:

R160/180/200 LONGNOSE DIFF MOUNT

The stock front differential mount on the Z is a source of constant exacerbation for Z owners. The diff mount does not have a failsafe built into it so by design when the mount comes apart there is nothing to prevent the nose of the diff from climbing. Nissan was kind enough to “fix” that problem by adding a strap over the top of the diff which helps limit the lifting at the front of the diff. These two parts combined do a marginal job of controlling the diff even under the “abuse” that stock power levels can put to them. Any increase in power levels should be accompanied by some attention to the front diff mount.

SOLID DIFF MOUNTS

These are sold by several aftermarket parts suppliers including http://www.arizonazcar.com and http://www.zcarparts.com. They will absolutely prevent the nose of the diff from lifting, but they also transmit lots of noise into the cabin, so much that some members here have reported feeling physically ill after only 10 minutes exposure to the noise. Regardless of these issues, this is a popular race part for Z cars, and there are quite a few people who do use these mounts on the street.

ALTERNATIVE DIFF MOUNTS

The creativity of our members cannot be overestimated and some of the easiest and simplest solutions to this problem come from our members’ garages. Probably the simplest solution comes from Clifton, who welded two tabs, one in front and one in back, to the vertical face of the diff mount. Then he drilled a hole in the tabs and ran a bolt through the two tabs. The bolt is trapped underneath the crossmember, so the diff can only lift until the bolt touches the crossmember. Simple solution and easy to make. I could not find a picture of this diff mount. I know I've seen it before. If you have a link post it up please.

Another good one is the clamshell design. A U shaped piece of metal is fitted below the front diff crossmember, and a rubber pad is installed on the new piece. This is then bolted or welded to the existing vertical flanges of the diff mount, similarly to Clifton’s solution. The advantage here is that the rubber isolates some noise from transmitting through the bolt and into the cabin. It’s possible a piece of fuel or radiator hose over the bolt in Clifton’s design might have just about the same effect. Click here for pictures and an explanation of the clamshell design: http://album.hybridz.org/showphoto.php?photo=2501

Either way both are simple and well worth the effort.

There is also Ron Tyler's design, which is more like the pinion snubber that you would find on an American car with a solid axle. This piece bolts to the chassis and the mount hangs down, where the diff bolts to it. This works great because the nose of the diff moves UP when torque is applied so torque doesn't rip the mount apart.

Pros:- It isn't solid, so you get vibration isolation ALL THE TIME.- It allows the front of the differential to be lowered so that the minimum and acceptable driveshaft u-joint angles can be obtained for a JTR V8 swap.- It allows you to modifiy/partially remove the front diff crossmember for mor exhaust clearance.- It bolts right in (in most cases).

Cons:- It requires welding.- It may take some massaging to fit into certain early 240Zs? So it may be best to build it on the car.- It uses no Nissan Parts? LOL

ALL PICTURES WERE TAKEN FROM THE HYBRIDZ ALBUM. IF YOU DON'T WANT YOUR PICTURE USED, LET ME KNOW AND I'LL REMOVE IT.]]>50499Sat, 04 Nov 2006 23:44:07 +0000Short nose R230 and R200 info and why.https://forums.hybridz.org/topic/64241-short-nose-r230-and-r200-info-and-why/Ok, there is STILL a lot of confusion on the short nose R200 differentials. These diffs have been out for a long time and there should NOT be anymore confusion. I am going to post up what I know is 100% fact. If I dont know, I will say. There is already a list of what diffs came in what cars. good info however, it is missing important info. Spline count. This is just going to cover the R200 and the R230's in which I know of. I didn't even know the Armada came with a 230, let alone a larger 230 than the TTZ

The 90-96 Q45 comes with a VLSD. I'm 99% sure the twin turbo Z also comes with a VLSD.

Now why are these two differentials so important? Because they are both have 30 spline input shafts, the R230 is splines are bigger diameter, (see post #14 below). Both are the desirable ones for making bigger power levels. When I say bigger, I mean like 700+ ft/lbs torque. That is big to some but not to others, so... This is a ball park on what they are good for. This ball park has HUGE variables though. If you launch your car and get nothing but wheel hop all over the place, no diff on the planet is going to like you. Generally it is not torque that breaks diffs, or ANY drive train parts for that matter(Yes there's exceptions). IT IS DRIVE LINE SHOCK that jacks things up. You do clutch drop after clutch drop, parts dont like you. You get wheel hop, parts dont like you. When you hear "Clunk" after doing something... that is bad. Respect your drive train and your drive train will respect you.

Now, back to the topic at hand. There are some misconceptions that need to be cleared up. The NON TURBO z32 DID NOT come with the R230. IT DOES NOT have the 6 bolt output flanges. It DOES have the same 5 bolt output flanges that most of the short nose R200's use. These come in the Infinity J30, the N/A z32 and later Q45's (97-02)) and as far as I know the 240sx (not as familiar with the 240sx). THESE ARE ALL 29 SPLINE!!!! Yes the 240sx as well, that I do know. The N/A z32 and the 97-02 Q45 DO come with a VLSD, again, it just has the smaller 29 spline with the 5 bolt output shaft. Only some of the 240sx's came with the VLSD, but I cant tell you which ones. As far as I know, any R200 that comes with some form of LSD is 4 pinion. Any open R200 is going to have 2 pinion. Again this is just as far as I know. I know for FACT that the 90-02 Q45 all use 4 pinion. I know for FACT that ALL z32's use 4 pinion.

NOW, the 2003 and on q45 (F50) comes with the six bolt equally spaced output flange also BUT I cannot tell you what spline count it has. I would assume it is also 30 spline but I have not pulled one to actually count it. It doesn't really matter though because of the following information that I KNOW is FACT.

The F50 Q45 diffs are NOT any kind of LSD. Not VLSD and not CLSD. They are an open diff. On top of that, they are only 2 pinion instead of the 4 pinion. Thats not good for anybody. Take that for what you will.

The reason I know this information is because of extensive internet searching. I kept coming across info that said one thing only to find someone else saying something else. The info I stated to be FACT can be backed up with pictures and FSM details.

Here is a picture of the NON TURBO z32 input shafts VS. the 90-96 Infinity Q45 input shafts. Notice the 5 bolt vs the 6 bolt also. also notice the diameter of the shafts, 29.8mm VS. 30.7mm. I came up with slightly different numbers but over all, it is 1mm difference. I got this picture from nismogab on z31performance.com

Here is what you will see if you look in the Q45 FSM's

90-96 Infinity Q45 R200 short nose. Notice the 4 pinions and 6 bolt along with the viscous coupling, Just like the Twin turbo z32's

97-02 Infinity Q45 R200 short nose. Notice the 4 pinion, but only 5 bolt, along with the viscous coupling, Just like the NA z32's

03- dont know how late Infinity Q45 R200 short nose. Notice the two pinion WITH NO viscous coupling! WEAK SAUCE!

I think that is about all I have to say about that.

]]>64241Mon, 03 Mar 2008 04:05:44 +0000FS5R30A Trannyhttps://forums.hybridz.org/topic/116553-fs5r30a-tranny/If I get an FS5R30A tranny from a Pathfinder instead of a 300ZX, will I have to change the gear ratio?

I know they are different on the Z32's, but unknown on the Pathfinder.

The only reason I care is this guy at a salvage yard is charging more for the one from the 300ZX. I assume because it's a sports car or more sought after. I'll take the cheaper Pathfinder one if it's workable that way.

]]>27605Tue, 18 May 2004 00:13:13 +0000What is the deal with solid diff mounts?https://forums.hybridz.org/topic/58895-what-is-the-deal-with-solid-diff-mounts/so i just ordered a new steering rack from msa and i was going to order a solid diff mount BUT the sales guy told me that it would transmit ALOT of harshness back into the car, and that the solid mount was mainly for race cars... now i want to know what personal experiences are with going with a solid mount.. i'm thinking about going with the arizona z car mount or the msa mount some advice would be appreciated]]>58895Sun, 19 Aug 2007 17:10:58 +0000Complete Differential List (need help)https://forums.hybridz.org/topic/38251-complete-differential-list-need-help/Complete Differential List (need help)

]]>40192Thu, 27 Oct 2005 16:20:40 +0000700R4 build that will survive 500ft/lbshttps://forums.hybridz.org/topic/115279-700r4-build-that-will-survive-500ftlbs/Ok guys so this is my first post as a new Z owner:

My problem: I have a Motor setup from my donor Camaro that is to be placed into the Z. It's a 383 Stroker laying down approx. 480HP at the crank, and about 500 ft lbs...this was previously mated to a TH350 that was built, and it handled it just fine (even with up to a 250 shot of N2O)

Now with the Z, I'm looking to go 700R4, as im making the car somewhat of a daily driver, but am not great with these transmissions and would like some input on what kind of work will be necessary to make this transmission survive my motor! (And maybe a small shot of nitrous on occasion)

I've already acquired my transmission, its a 1990 770r4 out of a 305 Camaro. And my next step is going to be buying the parts, I've come across this kit which seems to have everything:

"Super Master Rebuild KitThis kit is for 1987 to 1993 700R4 transmissions only. Here's what you get, the Fairbanks oversize billet intermediate servo and the Fairbanks oversize billet overdrive servo. The Sonnax oversize .500in. pressure valve and oversize low / reverse pressure valve. A 10 vane pump rotor and vane kit. Also included is a pump seal retainer and pump bushing, Borg Warner 29 element forward sprag, new low / reverse roller clutch, Alto carbon fiber Power Band. This kit comes with a torque converter lock-up kit, complete thrust washer kit and an Alto master rebuild kit. The master kit comes with all TransTec gaskets, seals and rings. You get a filter, Beast shell, 2 new accumulator pistons, Transgo separator plate. As an added bonus you get a discount plus freight in the 48 continental United States. After many years of research and development these parts where determined to work together best for a long lasting transmission."

Now, my questions is will this kit (in addition to a shift kit) give me everything necessary to achieve my goal? If not, what else should I look into? Experiences please! Thanks!

]]>115279Wed, 16 Oct 2013 05:13:20 +0000R230 Axle assembly: a pictoral reviewhttps://forums.hybridz.org/topic/25054-r230-axle-assembly-a-pictoral-review/While assembling a pair of axles for one of our esteemed members, I thought why not snap some pics while I go through the process? So here goes:

Step one: Get all parts:

2 pairs of Q45 axles

2 new shafts (Speedway Engineering)--Driver's side is slightly shorter.

A can of grease

A couple of rolls of paper shop towels (very messy job)

Step 2:Disassemble the old shafts:

After pulling back the boot, you will find a ring sitting in a groove inside the 'cup'. Scoop it out with a small srewdriver:

Step 3:Rip the guts out and clean away!!

Step 4:: Note the position of the cage. It can only be removed from the shaft after the 'C' clip and the 'hub' has been removed.:

Step 5: And this is what you'll get after cleaning (told you it was a messy job!!)

Step 6:Assemble the new shaft. Be sure to note that there is a machined area on the spline of the hub. That MUST go to the inside of the shaft (opposite side to the 'C' clip), otherwise no hammer in the world will get it on far enough to put the clip on (BTW.. the clip has a rounded edge and a flat edge. Make sure that the flat edge is facing out so that any force pushing on the clip is pushing the clip into the groove). For the first side it's not that important to remember to put on the boot and cage first because you'll have the unassembled side to access the hub, but the second side you will need to be more carefull

Step 7:Finish the assembly and grease it up. The balls will 'pop' in and the cage will hold them in place as long as it's straight. If you 'cokk' (misspelled intentionally otherwise it will come up as 'rooster' ) it the balls will fall out. Just hold them in place as you slide the assembly into the 'Cup'. Then slip the retaining ring back in and slide the boot in place and secure with the original clips.

Step 8: This what you get after repeating the process for the other side. A nice new axle and a bunch of trash!!

Tim

]]>25054Wed, 04 Feb 2004 23:43:07 +0000Adding Clutches to the CLSD R200https://forums.hybridz.org/topic/52029-adding-clutches-to-the-clsd-r200/This pretty basic for most of you I would assume. But I thought I would post up a step by step guide on rebuilding the clutch packs in the z31 R200 LSD.

First off here there are a couple great threads about this diffy floating around.

In summary a large problem with the nissan CLSD was that from the factory, presumably to save money, they only installed two clutches and filled the extra space in the clutch pack with two spacers. This, along with wear over time, makes many of these LSD's very weak with almost no breakaway torque. These spacers can be removed and replaced with extra clutches, to make the unit have a total of 6 clutches, how it should have come from the factory. Shims are then added to adjust the breakaway torque. The differential can also just be shimmed without the addition of clutchs for a quick fix.

Phyxius was kind enough to design and have new clutches cut from spring steel and offered them as a group buy here on hybrid. The stock units are now NLA. I used his clutches for my rebuild. Cant thank him enough for taking the time to draw these and have them made!

__________

Start by removing the rear diffy cover and the main bearing caps. This will alow the LSD unit to be pulled out. Its take a good bit of wiggling and working but will eventually come free, I used a wooden dowel and taped it easily through the axles holes to get it started.

KEEP TRACK OF THE SPACERS, the LSD unit is aligned in the case with spacers on both side. Take pictures and/or mark which side they go on.

Here is the LSD unit and the spacers laid out on the bench:

Next remove the ring gear, once hte bolts are removed It should slide off fairly easy with a few taps from a rubber mallet. I marked the position of mine relative to the LSD housing for safe measures. Once the ring gear is removed you will gain access to the four phillips screws that hold the unit together.

These can be a pain to get out as the unit is loaded. Grab a couple spare bolts and nuts and put them through the ring gear holes to take pressure off the screws. Once you get the screws out you can open the LSD housing and take out the internals. You will see:

spacer (which will be removed)

spring disc

spring disc

plate

clutch

plate

center section

plate

clutch

plate

spring disc

spring disc

spacer (which will be removed)

Heres a picture of the contents laid out on the work bench (sans spacers):

The discs with internal tabs are the clutches. The discs on the ends that look like plates are springs they are dished (kinda hard to see in the picture)

With the new clutches the unit will be assymbled as follows:

spring disc

spring disc

clutch

plate

clutch

plate

clutch

center section

clutch

plate

clutch

plate

clutch

spring disc

spring disc

This is just the beginning thoug heh. You must test the brekaway torque for the differential and shim it to your liking Here is an excellent site which has alot of information on the R200 LSD and specific information on testing:

I bought .004 SS shim stock from Mcmaster. I use the spacer as a template and cut the stock using a good pair of scissors. The shim will look like this:

Here is a picture of my testing apparatus using r200 stub axles:

I used a cheap ($10) beam style torque wrench from autozone to make the measurements. It was placed on the bar at the welded nut you see in the picture. All differentials are going be give slightly different results bases on the wear of the clutches and the thickness of the new clutches along with the co ef of friction provided by the type of oil you use,

however here are my results which may help as a baseline, I used Mobil 1 sythetic gear lube (75w-90) and Tran X LSD additive. I mixed up approximatly the amount that you would have in the differential to get the right ratio for testing.

A base line test without shims netted me 45 lb/ft for breakaway...

(.004 SS shims)

4 Shims - 60 ft-lbs

5 Shims - 75 ft-lbs

6 Shims - 90 ft-lbs

From research on this board and other sites, it seem that 60-75 ft-lbs is best suited for a street/autocross car perhaps you may want a little tighter for the track, its all your preference.

Putting it back together is the same as disasymbly, make sure the case marking on the LSD unit align and you get your bolts torque down to spec. Its a good idea to replace the axle seals as well while youve got the unit apart. Torque specs for the rear main caps are 65-72 ft-lbs.

Hope this helps some of you get started I wasnt sure what I was doing and thanks to JMortensen and others I got it figured out.

]]>52029Sat, 30 Dec 2006 06:04:36 +0000Rear end noisehttps://forums.hybridz.org/topic/108623-rear-end-noise/Just finished swapping a r180 with 4.11 in my 71 240z. Took it out for a test drive. It was running smooth until I took my foot off the throttle and let it coast. As soon as I let my foot off I hear this strange noise that sounds like it's coming from the right rear wheel. This sound only happens when I let off the throttle and let it coast. Everything looks ok. I'm not sure what the problem could be... Any ideas?]]>108623Thu, 23 Aug 2012 06:11:45 +0000https://forums.hybridz.org/topic/47635-alternate-bw-t5-clutch-slave-set-up/When I installed a CSB 350 together with a Borg-Warner T5 NWC gearbox in my 1972 240Z I followed the JTR manual almost to the letter.

As recommended by members on this board I used an 7/8" master cylinder (MC) from Wilwood (WIL-260-6765 at Summit). It fits the hole pattern in the firewall without trimming. I installed an AN4 fitting (like Summit RUS-66042-1) and a custom-made steel braided hose down to the stock GM plastic slave cylinder (SC).

The set up had several disadvantages. The connection to the plastic SC was fragile. I hade to hammer a bulge into the lower part of the fire wall to get sufficing clearance for the cutch arm.

It was so difficult to bleed. I didn't get it to work well. The clutch disengaged, but just barely.

The SC ended up very close to the down tub from the headers. I made an heat shield but it doubt it worked.

After just 1000 kilometers (625 miles) the SC quite and dumped all the fluid out around the pushrods. I was reluctant to just reinstall a new plastic SC so I started to investigate an alternative; and bellow is what I ended up with.

I used a SC with aluminum housing from Wilwood (WIL-260-1333 at Summit Racing). It is a pulling clutch SC so it needs a new mount and a modified clutch arm.

The stock clutch arm was shorted and an a hole drilled in it for the push rod

I fabricated a SC mount from 1/8" steel. I made some simple cardboard templates an the cut it out with a hack saw and bent it in a wise. It was then stick welded together. I made it to pick up on of the "ears" on the gearbox housing and two mounting bolts on the aft face of the gear box. It is a simple design and I hope the photos will aid if you wish to duplicate it.

The stock nipple on the Wilwood SC was replace with an other AN4 nipple and I had a new steel braided hose made. It is 800 mm (31.5") long and has 90 degree bend on both ends.

The rest of the photos shows the system installed. It works really well. It was simple to bleed and it disengages and engages distinctively. As can be seen from the photo it clears the firewall and the trans tunnel. It sits higher up in the trans tunnel an clears the exhaust tube with comfortable margin.

The disadvantages is that you must remove the bell housing from the engine to be able to remove and install the clutch arm and the clutch arm is hard as nails to drill in! Use a drill press, top quality drill bits, work slowly and use cutting fluid.

I have now put approx. 2000 km (1.250 miles) on it and it still works well, so I thought it would be something worthwhile sharing.

Best regards

ThomasZ

]]>47635Thu, 27 Jul 2006 19:38:06 +0000t-56 information neededhttps://forums.hybridz.org/topic/78043-t-56-information-needed/Man, I have had a heck of a time trying to find information for the t-56, and I know it's here, I've seen it before, gah... I've tried so many search types, and I have either been getting little to no results, or I'll get a bunch of LS1 conversions.

I was hoping that maybe we could create a sticky with anything you might need to know, like; dimensions, fluid capacity, preferred fluid types, inner shifter boots that fit the Z's, bellhousings/conversion kits, electrical plug part #'s, etc, and anything else that may seem valuable.

Hope fully this would help anyone else looking for similar information.

What I'm looking for is the preferred fluid. I was lookin at Amsoil, but it seems Royal Purple makes a good fluid too. Is there one in peticular that works well with the t-56?

Thanks

Ryan~

]]>78043Tue, 19 May 2009 17:07:28 +0000R230 first trial fit (pictures)https://forums.hybridz.org/topic/32312-r230-first-trial-fit-pictures/I drilled out a mustache bar with wider spaced holes and raised them as per suggestions found doing searches and raised the R230 in place. I have already purchased a billet 6061 aluminum plate that I am going to make a rear support out of and I have not cut the upper Transverse Link bushing perches off of the stock support yet since the stock rear support won't clear the cooling fins, but I bolted the support up on one side to test fit the TL for clearance. There are a number of issues that are showing up.

With the rear bolted up tight to the mustache bar, a small spacer will be needed as the curve of the cover hits the mustache bar, but I just bolted it up tight for the trial fit. In this position, the top of the rear hits the upper frame.

By moving the rear forward about 1/2 inch, (my custom cresent wrench spacer) , the rear clears the frame, but not by much.

I thought I read that someone flipped the mustache bar to push the rear forward, but that seems to me to be too extreme to keep the axles lined up properly.

The next issue is the transverse link contacts the axle flange. I mentioned in an earlier post http://forums.hybridz.org/showthread.php?t=96702 that the R230 is wider than the Q45 rear. This may be another issue of the wider flange spacing. It's hard to see in this picture, but even with the rear pushed forward 1/2" the flange touches the TL.

I think that maybe the end of the TL can be ground to clear, but it is TIGHT. I did not bolt up the TL tight, because it won't clear as it is. I still have to deal with the CV flange width added to whatever clearance issue that exists too.

The stock fuel pump (78 280) is on a plate that is hitting the front mount, and when you push the rear forward, it's worse. But maybe after clearancing the mounting plate and getting the front of the rear up where it needs to be, the TL issue will either correct itself, or it will require less grinding.

This was just the first trial fit to see what issues I will have to deal with. I have energy suspension bushings coming for the mustache bar and once they are here, I can bolt the mustache bar tight and begin spacing, clearancing and fabricating the front mount.

I would love to hear how far others positioned their R230 off of the mustache bar, and if anyone had to clearance their TL or any other fittment issues.